Wireless telegraphy.



UNrTED STATES ATENT Fries.'

HARRY SHOEMAKER, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO MARIE V. GEHRING, OF SAME PLACE.

WIRELESS TELEGRAPHY.

SPECIFICATION forming part of Letters Patent No. 671,407, dated April 2, 1901 Application led January 22, 1901. 4Serial. No. 44,270. (No model.)

To all whowt it nca/y concern:

Be it known that I, HARRY SHOEMAKER, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Wireless Telegraphy, of which the following is a speciication.

My invention relates to improvements in wireless telegraphy, and has special reference to animproved coherer, which is so constructed as to prevent the feathering of the pow dered metal and which is therefore reliable in its action, cohering and decohering perfectly.

Another object of my invention is thev provision of a coherer for wireless telegraphy so constructed and arranged that the resistance is materially lessened and the local current of electricity is varied.

To attain the desired objects, the invention consists of a coherer for the receiving-station of a wireless telegraph system embodying novel features of construction and combination of parts,substantially as disclosed herein.

In the drawings, Figure lis a small diagrammatical View of the transmitting and receiving stations of a wireless telegraph. Fig. 2 is a side elevation of a coherer. Fig. 3 is a front elevation thereof; and Fig. 4 is a view taken on lino a: of Fig. 3, the tubes and base not being shown.

Referring to the drawings, A designates the air-plate, and G designates the groundplate, having connection with the batteries B and the coherer. The coherer consists of the glass tubes C, supported between the arms D on thev standards D', and in these tubes are the necessary metallic powder E and silver plugs F, provided with the lower shouldered portions F'. Mounted below these tubes are the magnets H between the standards J. Connected to the core K of these magnets are the vertical plates or poles L, the end ones of which are provided with the bent ends or terminals M, which are directly opposite the V-shaped pockets of the tubes. The central pole is provided with the pair of oppositelyarranged bent ends or terminals N, making a T-shaped pole whose ends are directly opposite the pockets and the proper end of the other poles, so that a current of electricity passing through the magnets magnetizes these terminals and causes the powdered metal to be attracted therebetween.

The wires O are connected with the batteries B, thestandards D', the magnet H, and also with the electromagnet R2, which operates the lever R, which forms a circuit with the sounder P and batteries Q, as shown in Fig. l, said electromagnet R2 being a relaymagnet.

The transmitting-station is similar to any transmitting-station havingitsairand ground plates A and G', the batteries R', the Ruhmkorff coil S, and the operating-key T all in its proper circuit.

The operation of my system is readily understood; but, briey stated, it is as follows: The transmitting-key is operated and the impulse is transmitted through the coil S, the air-plate A', and the space to the air-plate A of the receiving-station. The impulse is then` transmitted to the tubes through the wires a, standards D', arms D, and to the ground through wire l). The coherer particles lose their resistance and permit the passage of current by means of the wires O to the decohering-magnet I-I and its poles from the batteries B to the electromagnet R2, which acts as a relay to operate the sounder-circuit.

My object in producing the decoheringmagnets as described is for the reason that when a single-pole magmet is employed the lines of force take a direction so as to thread out from the poles in nearly straight lines for a short distance. The effect upon the magnetic filings in the tubes is to string them out with the line of force and cause a bridging of Lheplugs, thus keeping the relay closed and rendering the instrument inoperative, while with the poles arranged as shown in the drawings the lines of force cut the tubes at right angles and lift the lings clear of the plugs, thus opening the relay-circuit to make the instrument operative and to overcome the defect in the single-pole magnets.

It will thus be seen thatI provide a coherer which is very simple in construction, andvby the construction of the poles and the arrangement of the magnets there is absolutely no danger of the powdered metallic particles adherin g to anything or becoming feathered and will cohere or decohere, as desired.

IOO

I claiml. In a Wireless telegraph, a transmitting and a receiving apparatus, said receiving apparatus comprising non-conducting tubes, oppositely-disposed conductor-p1u gs arranged Within the tubes and having their inner ends beveled to form a pocket, powdered particles of magnetic metal located in said pockets, a local circuit embracing said plugs and particles, and a magnet below said tubes and having the axis of its poles at right angles to the axis of the tubes and opposite the pockets thereof in said circuit arranged to act on said particles. I

2. A receiving apparatus for Wireless telegraphy, a coherer, comprising non-conducting tubes, alined conductor-plugs arranged within the tubes and having their separated inner ends far enough apart to form a pocket, magnetic particles located in said pocket, a local circuit embracing said plugs and magnetic\particles, a relay, and a magnet in said circuit having the axis of its poles at right angles to the axis of the tubes and opposite the pockets of the tubes arranged to act on said magnetic particles.

3. A coherer for Wireless telegraphy, consisting of a tube, alined conductor-plugs arranged within the tube and their separated ends far enough apart to form a pocket, magnetic particles located in said pocket, a circuit embracing said plugs and particles, and a magnet below said tube and having poles extending upward and at right angles to the axis of the tube and upon opposite sides of the tubes pockets to act-upon said particles.

4. A receiving apparatus for Wireless telegprising non-conducting tubes, alined cond uctor-plugs arranged Within the tubes and havtheir separated inner ends far enough apart to form a pocket, magnetic particles located in said pockets, a localcircuit embracing said plugs and magnetic particles, a relay, and a magnet having upwardly-extending arms or poles at right angles to the axis of the tubes and opposite the pockets of the tubes, said magnet in said'circuit.

5. A receiving apparatus for wi reless telegraphy, consisting of air and ground plates, a local circuit, a coherer, a relay anda magnet in said circuit; said magnet being located below said coherer and having upwardly -extending arms or poles at right angles to the axis of the coherer upon opposite sides thereof.

In testimony whereof I aiix my signature in presence of two witnesses.

HARRY S'I-IOEMAKER.

Witnesses:

WILLIAM J. Moss, R. LEAMAN.

= raphy, air and ground plates, a coherer, com- 

